This invention relates to container for wine and more particularly to a container whose internal volume may be reduced to minimize the exposure of the contained wine to the atmosphere as the wine is removed in increments from the container.
A number of arrangements have been used or proposed to deal with the problem of deterioration in the quality of wine which occurs as a result of exposure to air after the original wine bottle has been opened and some of the wine removed. One commercially successful arrangement is to put the wine in a plastic bag 10 which is marketed in a box 12 as shown in FIG. 1. A valve or spigot 14 sealed to the bag is accessible from outside the box for withdrawing wine as desired. The bag 10 collapses from the force of atmospheric pressure as the wine is withdrawn, so the remaining wine is minimally exposed to the air. Since the entire container is discarded when empty, this arrangement is somewhat expensive and is only used for packages of comparatively large quantity such as three liters or more.
Another method for dealing with the oxidation problem involves the use of a pump 16 attached to the opening of a wine bottle 18 as shown in FIG. 2. This pump is employed for the purpose of removing as much air as possible from the volume inside the bottle where air has displaced some of the wine. While this may be somewhat effective, there is a limit to how much of a vacuum can be created by such a simple pump.
There have been many patents describing a container having a hollow central tube with external threads and means engaged with the threads for forcing a piston into the container to cause the contents to be disposed out of the tube. One such apparatus is described in U.S. Pat. No. 5,028,960 to Seager. Most such devices are concerned with forcing heavy, viscous fluids such as greases or creams out of the container and are not concerned with oxidation of the contents.